MasonK wrote:I have yet to see any JHPs of any caliber fail to expand inside ballistics gel through denim and there is only one YouTube video I've ever seen where a JHP failed to expand when shot at a pig cadaver; oddly enough, that round was the Hornaday Critical Defence.
Ballistic gelatin is actually a very poor analog to the human body. The body contains bones, cartilage, varying densities and concentrations of fluid, and air cavities - all things that gelatin does not. A pig carcass is a much better analog to the human body, but still not perfect. The reality is that hollow point rounds fail to expand in human tissue 30-40% of the time.
FBI: Handgun wounding factors and effectiveness wrote: Handgun bullets expand in the human target only 60-70% of the time at best. Damage to the hollow point by hitting bone, glass, or other intervening obstacles can prevent expansion. Clothing fibers can wrap the nose of the bullet in a cocoon like manner and prevent expansion. Insufficient impact velocity caused by short barrels and/or longer range will prevent expansion, as will simple manufacturing variations. Expansion must never be the basis for bullet selection, but considered a bonus when, and if, it occurs. Bullet selection should be determined based on penetration first, and the unexpanded diameter of the bullet second, as that is all the shooter can reliably expect.
http://www.firearmstactical.com/pdf/fbi-hwfe.pdfIf a pig carcass were a perfect analog of the human body, and shot placement in the carcass performed the same as an upper center mass hit, you would expect to see a 30-40% rate of failure to expand.
Also, the reason that denim is used by bullet manufacturers in testing is that bullets tend to go through denim like a hot knife through butter. I'm not exactly sure why, probably because of the size of the cotton fibers, how they're wove together, etc. Almost all hollow point bullets can penetrate denim with very little loss of penetration, and then exhibit proper expansion in gel. A Navy pea coat behaves the opposite way, it tends to prevent expansion in gel more often than not as the fibers clog the bullet channel. Natural vs. man-made fibers, how they're wove, leather or suede, the thickness, etc. are all going to have different effects on a bullet that passes through it.
As the FBI recommends, bullet selection should be based on penetration first, diameter second, and only then should the expanding quality of a round be considered. All of the ballistic tests done by bullet manufacturers that demonstrate a large permanent wound cavity in gel should be taken with a grain of salt, as there is a very good chance that the bullet will simply fail to expand properly in human tissue. Also, the size of the permanent wound cavity only has an effect on the amount of blood loss, which is *not* a factor in the rounds ability to immediately stop the threat.
Take the case of MSG Roy Benavidez, in a single 6 hour incident in Vietnam he was shot 37 times, took grenade fragments to his back, was clubbed in the face with the butt of a rifle, and bayoneted across the abdomen. Not only was he able to survive these wounds while continuing to engage the enemy, but actually carried other team members while in this condition to an evac helocopter while holding his intestines in with his other hand. When his unit discovered years later that he had survived his wounds, he was nominated for and awarded the Congressional Medal of Honor by President Reagan. While extremely unusual, this shows that a persons body can suffer considerable tissue damage and loss of blood and still remain in the fight for a significant period of time.
http://www.psywarrior.com/benavidez.htmlhttp://www.youtube.com/watch?v=_oUtJxE4sjsAll the experts agree that the ability to stop a threat with a handgun round is more about placement of the round than any other factors, including caliber or expansion.
